克鲁格曼《国际经济学》(国际金融)习题标准答案要点
《国际经济学》教师手册及课后习题答案(克鲁格曼,第六版)imch13
HAPTER 13EXCHANGE RATES AND THE FOREIGN EXCHANGE MARKET: AN ASSET APPROACHChapter OrganizationExchange Rates and International TransactionsDomestic and Foreign PricesExchange Rates and Relative PricesBox: A Tale of Two DollarsThe Foreign Exchange MarketThe ActorsCharacteristics of the MarketSpot Rates and Forward RatesForeign Exchange SwapsFutures and OptionsThe Demand for Foreign Currency AssetsAssets and Asset ReturnsRisk and LiquidityInterest RatesExchange Rates and Asset ReturnsA Simple RuleReturn, Risk, and Liquidity in the Foreign Exchange MarketEquilibrium in the Foreign Exchange MarketInterest Parity: The Basic Equilibrium ConditionHow Changes in the Current Exchange Rate Affect Expected ReturnsThe Equilibrium Exchange RateInterest Rates, Expectations, and EquilibriumThe Effect of Changing Interest Rates on the Current Exchange RateThe Effect of Changing Expectations on the Current Exchange RateBox: The Perils of Forecasting Exchange RatesSummaryAppendix: Forward Exchange Rates and Covered Interest ParityCHAPTER OVERVIEWThe purpose of this chapter is to show the importance of the exchange rate in translating foreign prices into domestic values as well as to begin the presentation of exchange-rate determination. Central to the treatment of exchange-rate determination is the insight that exchange rates are determined in the same way as other asset prices. The chapter begins by describing how the relative prices of different countries' goods are affected by exchange rate changes. This discussion illustrates the central importance of exchange rates for cross-border economic linkages. The determination of the level of the exchange rate is modeled in the context of the exchange rate's role as the relative price of foreign and domestic currencies, using the uncovered interest parity relationship.The euro is used often in examples. Some students may not be familiar with the currency or aware of which countries use it; a brief discussion may be warranted. A full treatment of EMU and the theories surrounding currency unification appears in Chapter 20.The description of the foreign-exchange market stresses the involvement of large organizations (commercial banks, corporations, nonbank financial institutions, and central banks) and the highly integrated nature of the market. The nature of the foreign-exchange market ensures that arbitrage occurs quickly, so that common rates are offered worldwide. Forward foreign-exchange trading, foreign-exchange futures contracts and foreign-exchange options play an important part in currency market activity. The use of these financial instruments to eliminate short-run exchange-rate risk is described.The explanation of exchange-rate determination in this chapter emphasizes the modern view that exchange rates move to equilibrate asset markets. The foreign-exchange demand and supply curves that introduce exchange-rate determination in most undergraduate texts are not found here. Instead, there is a discussion of asset pricing and the determination of expected rates of return on assets denominated in different currencies.Students may already be familiar with the distinction between real and nominal returns. The text demonstrates that nominal returns are sufficient for comparing the attractiveness of different assets. There is a brief description of the role played by risk and liquidity in asset demand, but these considerations are not pursued in this chapter. (The role of risk is taken up again in Chapter 17.)Substantial space is devoted to the topic of comparing expected returns on assets denominated in domestic and foreign currency. The text identifies two parts of the expected return on a foreign-currency asset (measured in domestic-currency terms): the interest payment and the change in the value of the foreign currency relative to the domestic currency over the period in which the asset is held. The expected return on a foreign asset is calculated as a function of the current exchange rate for given expected values of the future exchange rate and the foreign interest rate.The absence of risk and liquidity considerations implies that the expected returns on all assets traded in the foreign-exchange market must be equal. It is thus a short step from calculations of expected returns on foreign assets to the interest parity condition. The foreign-exchange market is shown to be in equilibrium only when the interest parity condition holds. Thus, for given interest rates and given expectations about future exchange rates, interest parity determines the current equilibrium exchange rate. The interest parity diagram introduced here is instrumental in later chapters in which a more general model is presented. Since a command of this interest parity diagram is an important building block for future work, we recommend drills that employ this diagram.The result that a dollar appreciation makes foreign currency assets more attractive may appear counterintuitive to students -- why does a stronger dollar reduce the expected return on dollar assets? The key to explaining this point is that, under the static expectations and constant interest rates assumptions, a dollar appreciation today implies a greater future dollar depreciation; so, an American investor can expect to gain not only the foreign interest payment but also the extra return due to the dollar's additional future depreciation. The following diagram illustrates this point. In this diagram, the exchange rate at time t+1 is expected to be equal to E. If the exchange rate at time t is also E then expected depreciation is 0. If, however, the exchange rate depreciates at time t to E' then it must appreciate to reach E at time t+1. If the exchange rate appreciates today to E" then it must depreciate to reach E at time t+1. Thus, under static expectations, a depreciation today implies an expected appreciation and conversely.D om estic C urrencyF oreign C urrency E 'EE "Figure 13-1This pedagogic tool can be employed to provide some further intuition behind the interest parity relationship. Suppose that the domestic and foreign interest rates are equal. Interest parity then requires that expected depreciation is equal to zero and that the exchange rate today and next period is equal to E. If the domestic interest rate rises, people will want to hold more domestic-currency deposits. The resulting increased demand for domestic currency drives up the price of domestic currency, causing the exchange rate to appreciate. How long will this continue? The answer is that the appreciation of the domestic currency continues until the expected depreciation that is a consequence of the domestic currency's appreciation today just offsets the interest differential.The text presents exercises on the effects of changes in interest rates and of changes in expectations of the future exchange rate. These exercises can help develop students' intuition. For example, the initial result of a rise in U.S. interest rates is a higher demand for dollar-denominated assets and thus an increase in the price of the dollar. This dollar appreciation is large enough that the subsequent expected dollar depreciation just equalizes the expected return on foreign-currency assets (measured in dollar terms) and the higher dollar interest rate.The appendix describes the covered interest parity relationship and applies it to explain the determination of forward rates under risk neutrality as well as the high correlation between movements in spot and forward rates.ANSWERS TO TEXTBOOK PROBLEMS1. At an exchange rate of $1.50 per euro, the price of a bratwurst in terms of hot dogs is 3hot dogs per bratwurst. After a dollar appreciation to $1.25 per euro, the relative price of a bratwurst falls to 2.5 hot dogs per bratwurst.2. The Norwegian krone/Swiss franc cross rate must be 6 Norwegian krone per Swissfranc.3. The dollar rates of return are as follows:a. ($250,000 - $200,000)/$200,000 = 0.25.b. ($216 - $180)/$180 = 0.20.c. There are two parts of this return. One is the loss involved due to the appreciation ofthe dollar; the dollar appreciation is ($1.38 - $1.50)/$1.50 = -0.08. The other part of the return is the interest paid by the London bank on the deposit, 10 percent. (The size of the deposit is immaterial to the calculation of the rate of return.) In terms of dollars, the realized return on the London deposit is thus 2 percent per year.4. Note here that the ordering of the returns of the three assets is the same whether wecalculate real or nominal returns.a. The real return on the house would be 25% - 10% = 15%. This return could also becalculated by first finding the portion of the $50,000 nominal increase in the house's price due to inflation ($20,000), then finding the portion of the nominal increase due to real appreciation ($30,000), and finally finding the appropriate real rate of return ($30,000/$200,000 = 0.15).b. Again, subtracting the inflation rate from the nominal return we get 20%- 10% = 10%.c. 2% - 10% = -8%.5. The current equilibrium exchange rate must equal its expected future level since, withequality of nominal interest rates, there can be no expected increase or decrease in the dollar/pound exchange rate in equilibrium. If the expected exchange rate remains at $1.52 per pound and the pound interest rate rises to 10 percent, then interest parity is satisfied only if the current exchange rate changes such that there is an expected appreciation of the dollar equal to 5 percent. This will occur when the exchange rate rises to $1.60 per pound (a depreciation of the dollar against the pound).6. If market traders learn that the dollar interest rate will soon fall, they also reviseupward their expectation of the dollar's future depreciation in the foreign-exchange market. Given the current exchange rate and interest rates, there is thus a rise in the expected dollar return on euro deposits. The downward-sloping curve in the diagram below shifts to the right and there is an immediate dollar depreciation, as shown in the figure below where a shift in the interest-parity curve from II to I'I' leads to a depreciation of the dollar from E 0 to E 1.E($/euro i E 0 E 1Figure 13-2 7. The analysis will be parallel to that in the text. As shown in the accompanyingdiagrams, a movement down the vertical axis in the new graph, however, is interpreted as a euro appreciation and dollar depreciation rather than the reverse. Also, the horizontal axis now measures the euro interest rate. Figure 13-3 demonstrates that, given the expected future exchange rate, a rise in the euro interest rate from R 0 to R 1 will lead to a euro appreciation from E 0 to E 1.Figure 13-4 shows that, given the euro interest rate of i, the expectation of a stronger euro in the future leads to a leftward shift of the downward-sloping curve from II to I'I' and a euro appreciation (dollar depreciation) from E to E'. A rise in the dollar interest rate causes the same curve to shift rightward, so the euro depreciates against the dollar. This simply reverses the movement in figure 13-4, with a shift from I'I' to II, and a depreciation of the euro from E' to E. All of these results are the same as in the text when using the diagram for the dollar rather than the euro.EE 0rates o f return (in euro s) (euroE 101Figure 13-3Ei E (euro/$)E ’Figure 13-48. a. If the Federal Reserve pushed interest rates down, with an unchanged expected futureexchange rate, the dollar would depreciate (note that the article uses the term "downward pressure" to mean pressure for the dollar to depreciate). In terms of the analysis developed in this chapter, a move by the Federal Reserve to lower interest rates would be reflected in a movement from R to R' in figure 13.5, and a depreciation of the exchange rate from E to E'.If there is a "soft landing", and the Federal Reserve does not lower interest rates, thenthis dollar depreciation will not occur. Even if the Federal Reserve does lower interest rates a little, say from R to R", this may be a smaller decrease then what peopleinitially believed would occur. In this case, the expected future value of the exchange rate will be more appreciated than before, causing the interest-parity curve to shift in from II to I'I' (as shown in figure 13.6). The shift in the curve reflects the "optimism sparked by the expectation of a soft landing" and this change in expectations means that, with a fall in interest rates from R to R", the exchange rate depreciates from E to E", rather than from E to E *, which would occur in the absence of a change in expectations.ER ’ EE*Rrates of return (in dollars)EE Rrates of return (in dollars) E ”E *R ”Figure 13-6b.The "disruptive" effects of a recession make dollar holdings more risky. Risky assetsmust offer some extra compensation such that people willingly hold them as opposed to other, less risky assets. This extra compensation may be in the form of a bigger expected appreciation of the currency in which the asset is held. Given the expected future value of the exchange rate, a bigger expected appreciation is obtained by a more depreciated exchange rate today. Thus, a recession that is disruptive and makes dollar assets more risky will cause a depreciation of the dollar.9. The euro is less risky for you. When the rest of your wealth falls, the euro tends toappreciate, cushioning your losses by giving you a relatively high payoff in terms of dollars. Losses on your euro assets, on the other hand, tend to occur when they are least painful, that is, when the rest of your wealth is unexpectedly high. Holding the euro therefore reduces the variability of your total wealth.10. The chapter states that most foreign-exchange transactions between banks (whichaccounts for the vast majority of foreign-exchange transactions) involve exchanges of foreign currencies for U.S. dollars, even when the ultimate transaction involves the sale of one nondollar currency for another nondollar currency. This central role of the dollar makes it a vehicle currency in international transactions. The reason the dollar serves as a vehicle currency is that it is the most liquid of currencies since it is easy to find people willing to trade foreign currencies for dollars. The greater liquidity of the dollar as compared to, say, the Mexican peso, means that people are more willing to hold the dollar than the peso, and thus, dollar deposits can offer a lower interest rate, for any expected rate of depreciation against a third currency, than peso deposits for the same rate of depreciation against that third currency. As the world capital market becomes increasingly integrated, the liquidity advantages of holding dollar deposits as opposed to yen deposits will probably diminish. The euro represents an economy as large as the United States, so it is possible that it will assume some of that vehicle role of the dollar, reducing the liquidity advantages to as far as zero. Since the euro has no history as a currency, though, some investors may be leary of holding it until it has established a track record. Thus, the advantage may fade slowly.11. Greater fluctuations in the dollar interest rate lead directly to greater fluctuations in theexchange rate using the model described here. The movements in the interest rate can be investigated by shifting the vertical interest rate curve. As shown in figure 13.7,these movements lead directly to movements in the exchange rate. For example, an increase in the interest rate from i to i' leads to a dollar appreciation from E to E'. A decrease in the interest rate from i to i" leads to a dollar depreciation from E to E". This diagram demonstrates the direct link between interest rate volatility and exchange rate volatility, given that the expected future exchange rate does not change.EE($/foreign currency)rates of return (in dollars)iE ’i"i'E ”Figure 13-712. A tax on interest earnings and capital gains leaves the interest parity condition thesame, since all its components are multiplied by one less the tax rate to obtain after-tax returns. If capital gains are untaxed, the expected depreciation term in the interest parity condition must be divided by 1 less the tax rate. The component of the foreign return due to capital gains is now valued more highly than interest payments because it is untaxed.13. The forward premium can be calculated as described in the appendix. In this case, wefind the forward premium on euro to be (1.26 – 1.20)/1.20 = 0.05. The interest-rate difference between one-year dollar deposits and one-year euro deposits will be 5 percent because the interest difference must equal the forward premium on euro against dollars when covered interest parity holds.FURTHER READINGSJ. Orlin Grabbe. International Financial Markets, 3rd Edition. Englewood Cliffs: Prentice-Hall, 1996.Philipp Hartmann. Currency Competition and Foreign Exchange Rate Markets: The Dollar, the Yen, and the Euro. Cambridge: Cambridge University Press, 1999.John Maynard Keynes. A Tract on Monetary Reform. Chapter 3. London: Macmillan, 1923.Paul R. Krugman. "The International Role of the Dollar: Theory and Prospect." in John F.O. Bilson and Richard C. Marston, eds. Exchange Rate Theory and Practice. Chicago: University of Chicago Press, 1984, pp. 261-278.Richard Levich. International Financial Markets: Prices and Policies. Boston: Irwin McGraw-Hill, 1998.Richard K. Lyons. The Microstructure Approach to Exchange Rates. Cambridge: MIT Press, 2001.Ronald I. McKinnon. Money in International Exchange: The Convertible Currency System. New York: Oxford University Press, 1979.Michael Mussa. "Empirical Regularities in the Behavior of Exchange-rates and Theories of the Foreign-Exchange Market." in Karl Brunner and Allan H. Meltzer eds., Policies for Employment Prices and Exchange-Rates. Carnegie-Rochester Conference Series on Public Policy 11. Amsterdam: North-Holland Press, 1979.Julian Walmsley. The Foreign Exchange and Money Markets Guide. New York: John Wiley & Sons, 1992.99。
克鲁格曼《国际经济学》计算题及标准答案
1. 在古典贸易模型中,假设A 国有120名劳动力,B 国有50名劳动力,如果生产棉花的话,A 国的人均产量是2吨,B 国也是2吨;要是生产大米的话,A 国的人均产量是10吨,B 国则是16吨。
画出两国的生产可能性曲线并分析两国中哪一国拥有生产大米的绝对优势?哪一国拥有生产大米的比较优势?思路:B 国由于每人能生产16吨大米,而A 国每人仅生产10吨大米,所以B 国具有生产大米的绝对优势。
从两国生产可能性曲线看出A 国生产大米的机会成本为0.2,而B 国为0.125,所以B国生产大米的机会成本或相对成本低于A 国,B国生产大米具有比较优势。
2.下表列出了加拿大和中国生产1单位计算机和1单位小麦所需的劳动时间。
假定生产计算机和小麦都只用劳动,加拿大的总劳动为600小时,中国总劳动为800小时。
(1) 计算不发生贸易时各国生产计算机和小麦的产量。
(2) 哪个国家具有生产计算机的比较优势?哪个国家具有生产小麦的比较优势?(3) 如果给定世界价格是1单位计算机交换22单位的小麦,加拿大参与贸易可以从每单位的进口中节省多少劳动时间?中国可以从每单位进口中节省多少劳动时间?如果给定世界价格是1单位计算机交换24单位的小麦,加拿大和中国分别可以从进口每单位的货物中节省多少劳动时间?(4) 在自由贸易的情况下,各国应生产什么产品,数量是多少?整个世界的福利水平是提高还是降低了?试用图分析。
(以效用水平来衡量福利水平)思路:(1) 中国生产计算机的机会成本为100/4=25,加拿大为60/3=20(2) 因为加拿大生产计算机的机会成本比中国低,所以加拿大具有生产者计算机的比较优势,中国就具有生产小麦的比较优势。
(3) 如果各国按照比较优势生产和出口,加拿大进口小麦出口计算机,中国进口计算机出口小麦。
加拿大进口一单位小麦需要出口1/22单位计算机,折合成劳动时间来算,生产一单位小麦本国要用3小时,但生产1/22单位计算机本国要用60/22小时劳动,所以加拿大进口一单位小麦相当于用60/22小时的劳动换回本国3小时生产的产品,节省了3-60/22=3/11小时的劳动时间。
国际经济学克鲁格曼课后习题答案章完整版
国际经济学克鲁格曼课后习题答案章集团标准化办公室:[VV986T-J682P28-JP266L8-68PNN]第一章练习与答案1.为什么说在决定生产和消费时,相对价格比绝对价格更重要?答案提示:当生产处于生产边界线上,资源则得到了充分利用,这时,要想增加某一产品的生产,必须降低另一产品的生产,也就是说,增加某一产品的生产是有机会机本(或社会成本)的。
生产可能性边界上任何一点都表示生产效率和充分就业得以实现,但究竟选择哪一点,则还要看两个商品的相对价格,即它们在市场上的交换比率。
相对价格等于机会成本时,生产点在生产可能性边界上的位置也就确定了。
所以,在决定生产和消费时,相对价格比绝对价格更重要。
2.仿效图1—6和图1—7,试推导出Y商品的国民供给曲线和国民需求曲线。
答案提示:3.在只有两种商品的情况下,当一个商品达到均衡时,另外一个商品是否也同时达到均衡?试解释原因。
答案提示:4.如果生产可能性边界是一条直线,试确定过剩供给(或需求)曲线。
答案提示:5.如果改用Y商品的过剩供给曲线(B国)和过剩需求曲线(A国)来确定国际均衡价格,那么所得出的结果与图1—13中的结果是否一致?6.答案提示:国际均衡价格将依旧处于贸易前两国相对价格的中间某点。
7.说明贸易条件变化如何影响国际贸易利益在两国间的分配。
答案提示:一国出口产品价格的相对上升意味着此国可以用较少的出口换得较多的进口产品,有利于此国贸易利益的获得,不过,出口价格上升将不利于出口数量的增加,有损于出口国的贸易利益;与此类似,出口商品价格的下降有利于出口商品数量的增加,但是这意味着此国用较多的出口换得较少的进口产品。
对于进口国来讲,贸易条件变化对国际贸易利益的影响是相反的。
8.如果国际贸易发生在一个大国和一个小国之间,那么贸易后,国际相对价格更接近于哪一个国家在封闭下的相对价格水平?答案提示:贸易后,国际相对价格将更接近于大国在封闭下的相对价格水平。
克鲁格曼《国际经济学》(第8版)课后习题详解(第11章贸易政策中的争议)【圣才出品】
克鲁格曼《国际经济学》(第8版)课后习题详解(第11章贸易政策中的争议)【圣才出品】第11章贸易政策中的争议一、概念题1.以邻为壑的政策(beggar-thy-neighbor policies)答:以邻为壑的政策是指以牺牲别国的利益来提高本国福利的政策,即当一个国家采取某种政策或行动的时候,事实上其得到的好处来自于另一个国家的损失,一个国家所得到的,最终会是另一个国家所失去的。
从货币角度来说,本国货币扩张会引起汇率贬值,净出口增加,从而增加产出与就业,但是本国增加净出口对应着国外贸易余额的恶化。
本国货币贬值使需求从国外商品转移到本国商品上,国外的产出与就业会因此下降。
正是由于这个原因,由贬值引起的贸易余额的变动就是以邻为壑的政策,它是输出失业,或以损害其他国家来创造本国就业的一种方式。
本国福利的提高是以牺牲别国利益为代价的,因此这一政策很容易引起别国的报复和贸易战的爆发,最终损害各方的利益。
从国际贸易角度来说,战略性贸易政策就是一种以邻为壑的政策。
战略性贸易政策通过鼓励国内特定产品的出口和限制国外特定产品的进口,来保持本国在世界市场上的竞争优势,虽然使本国受益,但使外国受到了损失,本国也面临着受到外国报复的问题。
反之,如果外国的净出口增加,相当于本国消费者购买了很多外国的商品。
这样,对本国该产业的产品需求的下降就是对本国的该产业的一个冲击。
这种冲击会阻碍对其进行的投资和经营,从而使得这个产业的状况变坏,进而影响本国经济。
总之,以邻为壑的政策将引发贸易战从而使得各方均受到损害。
2.外部性(externalities)答:外部性是指当某个企业的经济行为(或者某个人的消费行为),经过非价格手段,直接地、不可避免地影响了其他企业的生产(或者其他人的效用),并且成为后者自己所不能加以控制的情况时,对前者来说就存在着外部性问题。
外部性可以分为正外部性和负外部性。
正外部性是指某个经济行为主体的行为使他人或者整个社会受益,而受益者无须花费代价;负外部性是指某经济行为主体的行为引起他人成本的增加或者效用的减少。
克鲁格曼《国际经济学》(国际金融部分)课后习题答案(英文版)第一章
克鲁格曼《国际经济学》(国际金融部分)课后习题答案(英文版)第一章CHAPTER 1INTRODUCTIONChapter OrganizationWhat is International Economics About?The Gains from TradeThe Pattern of TradeProtectionismThe Balance of PaymentsExchange-Rate DeterminationInternational Policy CoordinationThe International Capital MarketInternational Economics: Trade and MoneyCHAPTER OVERVIEWThe intent of this chapter is to provide both an overview of the subject matter of international economics and to provide a guide to the organization of the text. It is relatively easy for an instructor to motivate the study of international trade and finance. The front pages of newspapers, the covers of magazines, and the lead reports of television news broadcasts herald the interdependence of the U.S. economy with the rest of the world. This interdependence may also be recognized by students through their purchases of imports of all sorts of goods, their personal observations of the effects of dislocations due to international competition, and their experience through travel abroad.The study of the theory of international economics generates an understanding of many key events that shape our domesticand international environment. In recent history, these events include the causes and consequences of the large current account deficits of the United States; the dramatic appreciation of the dollar during the first half of the 1980s followed by its rapid depreciation in the second half of the 1980s; the Latin American debt crisis of the 1980s and the Mexico crisis in late 1994; and the increased pressures for industry protection against foreign competition broadly voiced in the late 1980s and more vocally espoused in the first half of the 1990s. Most recently, the financial crisis that began in East Asia in 1997 andspread to many countries around the globe and the Economic and Monetary Union in Europe have highlighted the way in which various national economies are linked and how important it is for us to understand these connections. At the same time, protests at global economic meetings have highlighted opposition to globalization. The text material will enable students to understand the economic context in which such events occur.Chapter 1 of the text presents data demonstrating the growth in trade and increasing importance of international economics. This chapter also highlights and briefly discusses seven themes which arise throughout the book. These themes include: 1) the gains from trade;2) the pattern of trade; 3) protectionism; 4), the balance of payments; 5) exchange rate determination; 6) international policy coordination; and 7) the international capital market. Students will recognize that many of the central policy debates occurring today come under the rubric of one of these themes. Indeed, it is often a fruitful heuristic to use current events to illustrate the force of the key themes and arguments which are presentedthroughout the text.。
克鲁格曼《国际经济学》(国际金融)习题标准答案要点
克鲁格曼《国际经济学》(国际金融)习题答案要点————————————————————————————————作者:————————————————————————————————日期:23 《国际经济学》(国际金融)习题答案要点第12章 国民收入核算与国际收支1、如问题所述,GNP 仅仅包括最终产品和服务的价值是为了避免重复计算的问题。
在国民收入账户中,如果进口的中间品价值从GNP 中减去,出口的中间品价值加到GNP 中,重复计算的问题将不会发生。
例如:美国分别销售钢材给日本的丰田公司和美国的通用汽车公司。
其中出售给通用公司的钢材,作为中间品其价值不被计算到美国的GNP 中。
出售给日本丰田公司的钢材,钢材价值通过丰田公司进入日本的GNP ,而最终没有进入美国的国民收入账户。
所以这部分由美国生产要素创造的中间品价值应该从日本的GNP 中减去,并加入美国的GNP 。
2、(1)等式12-2可以写成()()p CA S I T G =-+-。
美国更高的进口壁垒对私人储蓄、投资和政府赤字有比较小或没有影响。
(2)既然强制性的关税和配额对这些变量没有影响,所以贸易壁垒不能减少经常账户赤字。
不同情况对经常账户产生不同的影响。
例如,关税保护能提高被保护行业的投资,从而使经常账户恶化。
(当然,使幼稚产业有一个设备现代化机会的关税保护是合理的。
)同时,当对投资中间品实行关税保护时,由于受保护行业成本的提高可能使该行业投资下降,从而改善经常项目。
一般地,永久性和临时性的关税保护有不同的效果。
这个问题的要点是:政策影响经常账户方式需要进行一般均衡、宏观分析。
3、(1)、购买德国股票反映在美国金融项目的借方。
相应地,当美国人通过他的瑞士银行账户用支票支付时,因为他对瑞士请求权减少,故记入美国金融项目的贷方。
这是美国用一个外国资产交易另外一种外国资产的案例。
(2)、同样,购买德国股票反映在美国金融项目的借方。
当德国销售商将美国支票存入德国银行并且银行将这笔资金贷给德国进口商(此时,记入美国经常项目的贷方)或贷给个人或公司购买美国资产(此时,记入美国金融项目的贷方)。
《国际经济学》克鲁格曼(第六版)习题答案imsect3
OVERVIEW OF SECTION III: EXCHANGE RATES AND OPEN ECONOMY MACROECONOMICSSection III of the textbook is comprised of six chapters:Chapter 12 National Income Accounting and the Balance of PaymentsChapter 13 Exchange Rates and the Foreign Exchange Market: An Asset Approach Chapter 14 Money, Interest Rates, and Exchange RatesChapter 15 Price Levels and the Exchange Rate in the Long RunChapter 16 Output and the Exchange Rate in the Short RunChapter 17 Fixed Exchange Rates and Foreign Exchange InterventionSECTION III OVERVIEWThe presentation of international finance theory proceeds by building up an integrated model of exchange rate and output determination. Successive chapters in Part III construct this model step by step so students acquire a firm understanding of each component as well as the manner in which these components fit together. The resulting model presents a single unifying framework admitting the entire range of exchange rate regimes from pure float to managed float to fixed rates. The model may be used to analyze both comparative static and dynamic time path results arising from temporary or permanent policy or exogenous shocks in an open economy.The primacy given to asset markets in the model is reflected in the discussion of national income and balance of payments accounting in the first chapter of this section. Chapter 12 begins with a discussion of the focus of international finance. The discussion then proceeds to national income accounting in an open economy. The chapter points out, in the discussion on the balance of payments account, that current account transactions must be financed by financial account flows from either central bank or noncentral bank transactions. A case study uses national income accounting identities to consider the link between government budget deficits and the current account.Observed behavior of the exchange rate favors modeling it as an asset price rather than as a goods price. Thus, the core relationship for short-run exchange-rate determination in the model developed in Part III is uncovered interest parity. Chapter 13 presents a model inwhich the exchange rate adjusts to equate expected returns on interest-bearing assets denominated in different currencies given expectations about exchange rates, and the domestic and foreign interest rate. This first building block of the model lays the foundation for subsequent chapters that explore the determination of domestic interest rates and output, the basis for expectations of future exchange rates and richer specifications of the foreign-exchange market that include risk. An appendix to this chapter explains the determination of forward exchange rates.Chapter 14 introduces the domestic money market, linking monetary factors to short-run exchange-rate determination through the domestic interest rate. The chapter begins with a discussion of the determination of the domestic interest rate. Interest parity links the domestic interest rate to the exchange rate, a relationship captured in a two-quadrant diagram. Comparative statics employing this diagram demonstrate the effects of monetary expansion and contraction on the exchange rate in the short run. Dynamic considerations are introduced through an appeal to the long run neutrality of money that identifies a long-run steady-state value toward which the exchange rate evolves. The dynamic time path of the model exhibits overshooting of the exchange-rate in response to monetary changes.Chapter 15 develops a model of the long run exchange rate. The long-run exchange rate plays a role in a complete short-run macroeconomic model since one variable in that model is the expected future exchange rate. The chapter begins with a discussion of the law of one price and purchasing power parity. A model of the exchange rate in the long-run based upon purchasing power parity is developed. A review of the empirical evidence, however, casts doubt on this model. The chapter then goes on to develop a general model of exchange rates in the long run in which the neutrality of monetary shocks emerges as a special case. In contrast, shocks to the output market or changes in fiscal policy alter the long run real exchange rate. This chapter also discusses the real interest parity relationship that links the real interest rate differential to the expected change in the real exchange rate. An appendix examines the relationship of the interest rate and exchange rate under a flexible-price monetary approach.Chapter 16 presents a macroeconomic model of output and exchange-rate determination in the short run. The chapter introduces aggregate demand in a setting of short-run price stickiness to construct a model of the goods market. The exchange-rate analysis presented in previous chapters provides a model of the asset market. The resulting model is, in spirit, very close to the classic Mundell-Fleming model. This model is used to examine the effects of avariety of policies. The analysis allows a distinction to be drawn between permanent and temporary policy shifts through the pedagogic device that permanent policy shifts alter long-run expectations while temporary policy shifts do not. This distinction highlights the importance of exchange-rate expectations on macroeconomic outcomes. A case study of U.S. fiscal and monetary policy between 1979 and 1983 utilizes the model to explain notable historical events. The chapter concludes with a discussion of the links between exchange rate and import price movements which focuses on the J-curve and exchange-rate pass-through. An appendix to the chapter compares the IS-LM model to the model developed in this chapter. A second appendix considers intertemporal trade and consumption demand. A third appendix discusses the Marshall-Lerner condition and estimates of trade elasticities.The final chapter of this section discusses intervention by the central bank and the relationship of this policy to the money supply. This analysis is blended with the previous chapter's short-run macroeconomic model to analyze policy under fixed rates. The balance sheet of the central bank is used to keep track of the effects of foreign exchange intervention on the money supply. The model developed in previous chapters is extended by relaxing the interest parity condition and allowing exchange-rate risk to influence agents' decisions. This allows a discussion of sterilized intervention. Another topic discussed in this chapter is capital flight and balance of payments crises with an introduction to different models of how a balance of payments or currency crisis can occur. The analysis also is extended to a two-country framework to discuss alternative systems for fixing the exchange-rate as a prelude to Part IV. An appendix to Chapter 17 develops a model of the foreign-exchange market in which risk factors make domestic-currency and foreign-currency assets imperfect substitutes.A second appendix explores the monetary approach to the balance of payments. The third appendix discusses the timing of a balance of payments crisis.。
克鲁格曼《国际经济学》笔记和课后习题详解(国民收入核算与国际收支平衡)【圣才出品】
克鲁格曼《国际经济学》笔记和课后习题详解(国民收⼊核算与国际收⽀平衡)【圣才出品】⼗万种考研考证电⼦书、题库、视频学习平台第12章国民收⼊核算与国际收⽀平衡12.1 复习笔记1.国民收⼊账户(1)GNP宏观经济分析的主要着眼点是⼀国的国民⽣产总值(GNP),它是⼀国的⽣产要素在⼀定时期内所⽣产并在市场上卖出的最终商品和服务的价值总量。
GNP是宏观经济学家研究⼀国产出时所⽤的基本度量⼿段,由花费在最终产品上的⽀出的市场价值量加总⽽得到。
GNP的⽀出与劳动、资本以及其他⽣产要素紧密相连。
根据购买最终产品的四种可能⽤途,GNP可以分解为以下四个部分:消费(国内居民私⼈消费的数额)、投资(私⼈企业为进⾏再⽣产⽽留下的⽤于购买⼚房设备的数额)、政府购买(政府使⽤的数额)和经常项⽬余额(对外净出⼝的商品和服务的数额)。
(2)国民收⼊国民收⼊等于GNP减去折旧,加上净单边转移⽀付,再减去间接商业税。
即:国民收⼊=GNP-折旧+净单边转移⽀付-间接商业税在实际经济中,要使GNP和国民收⼊的恒等关系完全成⽴,必须对GNP的定义作⼀定调整:①GNP不考虑机器和建筑物在使⽤过程中由于磨损⽽引起的经济损失。
这部分经济损失称为折旧,折旧减少了资本所有者的收⼊。
为了计算⼀定时期的国民收⼊,必须从GNP 中减去这⼀时期资本的折旧。
GNP减去折旧后称为国民⽣产净值(NNP)。
⼗万种考研考证电⼦书、题库、视频学习平台②⼀国的收⼊可能会包括外国居民的赠与,这种赠与称为单边转移⽀付。
单边转移⽀付的例⼦包括向居住在国外的退休公民⽀付养⽼⾦、赔偿⽀付和对遭受旱灾国家的救济援助等。
净单边转移⽀付是⼀国收⼊的⼀部分,但不是⼀国产出的⼀部分,因此,净单边转移⽀付,必须加到NNP中以计算国民收⼊。
③国民收⼊取决于⽣产者获得的产品价格,GNP则取决于购买者所⽀付的价格。
但是,这两组价格并不是完全⼀致的,例如,销售税会使得购买者的⽀付⼤于销售者的收⼊,导致GNP被⾼估,超过了国民收⼊。
克鲁格曼《国际经济学》(第8版)课后习题详解(第7章国际要素流动)【圣才出品】
克鲁格曼《国际经济学》(第8版)课后习题详解(第7章国际要素流动)【圣才出品】第7章国际要素流动⼀、概念题1.外国直接投资(direct foreign investment)答:外国直接投资⼜称“海外直接投资”,是指⼀个国家或地区的投资者对另⼀国家或地区所进⾏的、以控制或参与经营管理为特征的跨国投资⾏为,是国际资本流动的⼀种重要形式。
跨国公司是最主要的直接投资主体之⼀。
外国直接投资有多种具体形式,常见的有直接在国外投资设⽴⼦公司或分公司、购买国外某公司全部或⼀定⽐例的股份并获得⼀定的控制权、通过与东道国企业签订各种合约或合同取得对该企业的某种控制权等。
2.跨国公司的分布及内部化动机(location and internalization motives of multinationals)答:内部化是指在企业内部建⽴市场,以企业的内部市场代替外部市场,从⽽解决由于市场不完全⽽带来的不能保证供需交换正常进⾏的问题的⾏为过程。
内部化理论认为,由于市场存在不完全性和交易成本上升,因此企业通过外部市场的买卖关系不能保证企业获利,并导致许多附加成本。
因此,建⽴企业内部市场即通过跨国公司内部形成的公司内市场,就能克服外部市场和市场不完全所造成的风险和损失,给技术转移和垂直⼀体化带来好处。
3.要素流动(factor movements)答:要素流动是指⽣产要素在不同国家之间的流动。
具体包括劳动⼒流动、国际借贷和证券投资等形式的短期资本流动,以及跨国公司进⾏的长期投资等。
就经济本⾝⽽⾔,⽣产要素的国际流动和商品的国际流动(国际贸易)没有本质的不同,⼆者在⼀定程度上是可以相互替代的;但在现实⽣活中,由于社会、政治和⽂化传统等⽅⾯的差异,⽣产要素的国际流动远⽐商品的国际流动困难和复杂。
如今,商品的国际流动越来越便捷,但⽣产要素的国际流动还有很多限制:⼤多数国家仍对移民做出严格的限制,东道国对国际资本短期流动的投机性和冲击⼒提⾼了警惕,⼤多数国家对跨国公司进⾏直接投资的领域和股权⽐例做出了限制性规定等。
克鲁格曼《国际经济学》(第8版)课后习题详解
克鲁格曼《国际经济学》(第8版)课后习题详解克鲁格曼《国际经济学》(第8版)课后习题详解克鲁格曼《国际经济学》(第8版)课后习题详解第1章绪论本章不是考试的重点章节,建议读者对本章内容只作大致了解即可,本章没有相关的课后习题。
第1篇国际贸易理论第2章世界贸易概览一、概念题1>(发展中国家(developing countries)答:发展中国家是与发达国家相对的经济上比较落后的国家,又称“欠发达国家”或“落后国家”。
通常指第三世界国家,包括亚洲、非洲、拉丁美洲及其他地区的130多个国家。
衡量一国是否为发展中国家的具体标准有很多种,如经济学家刘易斯和世界银行均提出过界定发展中国家的标准。
一般而言,凡人均收入低于美国人均收入的五分之一的国家就被定义为发展中国家。
比较贫困和落后是发展中国家的共同特点。
2>(服务外包(service outsourcing)答:服务外包是指企业将其非核心的业务外包出去,利用外部最优秀的专业化团队来承接其业务,从而使其专注于核心业务,达到降低成本、提高效率、增强企业核心竞争力和对环境应变能力的一种管理模式。
20世纪90年代以来,随着信息技术的迅速发展,特别是互联网的普遍存在及广泛应用,服务外包得到蓬勃发展。
从美国到英国,从欧洲到亚洲,无论是中小企业还是跨国公司,都把自己有限的资源集中于公司的核心能力上而将其余业务交给外部专业公司,服务外包成为“发达经济中不断成长的现象”。
3>(引力模型(gravity model)答:丁伯根和波伊赫能的引力模型基本表达式为:其中,是国与国的贸易额,为常量,是国的国内生产总值,是国的国内生产总值,是两国的距离。
、、三个参数是用来拟合实际的经济数据。
引力模型方程式表明:其他条件不变的情况下,两国间的贸易规模与两国的GDP成正比,与两国间的距离成反比。
把整个世界贸易看成整体,可利用引力模型来预测任意两国之间的贸易规模。
另外,引力模型也可以用来明确国际贸易中的异常现象。
(完整版)克鲁格曼国际经济学答案
Chapter 61.For each of the following examples, explain whether this is a case of external or internaleconomies of scale:a.Most musical wind instruments in the United States are produced by more than adozen factories in Elkhart, Indiana.b.All Hondas sold in the United States are either imported or produced in Marysville,Ohio.c.All airframes for Airbus, Europe’s only producer of large aircraft, are assembled inToulouse, France.d.Hartford, Connecticut is the insurance capital of the northeastern United States.External economies of scale: Cases a and d. The productions of these two industries concentrate in a few locations and successfully reduce each industry's costs even when the scale of operation of individual firms remains small. External economies need not lead to imperfect competition. The benefits of geographical concentration may include a greater variety of specialized services to support industry operations and larger labor markets or thicker input markets.Internal economies of scale: Cases b and c. Both of them occur at the level of the individual firm. The larger the output of a product by a particular firm, the lower its average costs. This leads to imperfect competition as in petrochemicals, aircraft, and autos.2.In perfect competition, firm set price equal to marginal cost. Why isn’t this possiblewhen there are internal economies of scale?Unlike the case of perfectly competitive markets, under monopoly marginal revenue is not equal to price. The profit maximizing output level of a monopolist occurs where marginal revenue equals marginal cost. Marginal revenue is always less than price under imperfectly competitive markets because to sell an extra unit of output the firm must lower the price of all units, not just the marginal one.3.It is often argued that the existence of increasing returns is a source of conflict betweencountries, since each country is better off if it can increase its production in those industries characterized by economies of scale. Evaluate this view in terms of both the monopolistic competition and the external economy models.Both internal economies of scale (which may lead to monopolistic competition) and external economies of scale could lead to increasing returns.By concentrating the production of each good with economies of scale in one country rather than spreading the production over several countries, the world economy will use the same amount of labor to produce more output.In the monopolistic competition model, the concentration of labor benefits the host country.The host country can capture some monopoly rents. But the rest of the world may hurt and have to face higher prices on its consumption goods.In the external economies case, such monopolistic pricing behavior is less likely since imperfectly competitive markets are less likely.4.Suppose the two countries we considered in the numerical example on pages 132-135were to integrate their automobile marker with a third country with an annual market for 3.75 million automobiles. Find the number of firms, the output per firm, and theprice per automobile in the new integrated market after trade.15.8n X 1c P c AC 2=⇒==−−→−+=+==nS Fb S n bn X F AC P However, since you will never see 0.8 firms, there will be 15 firms that enter the market, not16 firms since the last firm knows that it can not make positive profits. The rest of the solution is straight-forward. Using X=S/n, output per firm is 41,666 units. Using the price equation, and the fact that c=5,000, yields an equilibrium price of $7,000.5.Evaluate the relative importance of economies of scale and comparative advantage incausing the following:a.Most of the world’s aluminum is smelted in Norway or Canada.b.Half of the world’s large jet aircraft are assembled in Seattle.c.Most semiconductors are manufactured in either the United States or Japan.d.Most Scotch whiskey comes from Scotland.e.Much of the world’s best wine comes from France.a. The relatively few locations for production suggest external economies of scale in production. If these operations are large, there may also be large internal economies of scale in production.b. Since economies of scale are significant in airplane production, it tends to be done by a small number of (imperfectly competitive) firms at a limited number of locations. One such location is Seattle, where Boeing produces.c. Since external economies of scale are significant in semiconductor production, semiconductor industries tend to be concentrated in certain geographic locations. If, for some historical reason, a semiconductor is established in a specific location, the export of semiconductors by that country is due to economies of scale and not comparative advantage.d. "True" scotch whiskey can only come from Scotland. The production of scotch whiskey requires a technique known to skilled distillers who are concentrated in the region. Also, soil and climactic conditions are favorable for grains used in local scotch production. This reflects comparative advantage.e. France has a particular blend of climactic conditions and land that is difficult to reproduce elsewhere. This generates a comparative advantage in wine production.6.There are some shops in Japan that sell Japanese goods imported back from the UnitedStates at a discount over the prices charged by other Japanese shops. How is this possible?The Japanese producers employ price discrimination across United States and Japanesemarkets, so that the goods sold in the United States are much cheaper than those sold in Japan. It may be profitable for other Japanese to purchase these goods in the United States, incur any tariffs and transportation costs, and resell the goods in Japan. Clearly, the price differential across markets may lead to such profitable chance.7.Consider a situation similar to that in Figure 6-9, in which two countries that canproduce a good are subject to forward-falling supply curves. In this case, however, suppose that the two countries have the same costs, so that their supply curves are identical.a.What would you expect to be the pattern of international specialization and trade?What would determine who produces the good?QP,CD AC AC External Economics and SpecializationSuppose two countries that can produce a good are subject to forward-falling supply curves and are identical countries with identical curves. If one country starts out as a producer of a good, i.e. it has a head start even as a matter of historical accident, then all production will occur in that particular country and it will export to the rest of the world.b.What are the benefits of international trade in this case? Do they accrue only to thecountry that gets the industry?Consumers in both countries will pay a lower price for this good when externaleconomies are maximized through trade and all production is located in a single market. In the present example, no single country has a natural cost advantage or is worse off than it would be under autarky.8.It is fairly common for an industrial cluster to break up and for production to move tolocations with lower wages when the technology of the industry is no longer rapidly improving—when it is no longer essential to have the absolutely most modern machinery, when the need for highly skilled workers has declined, and when being at the cutting edge of innovation conveys only a small advantage. Explain this tendency of industrial clusters to break up in terms of the theory of external economies.External economies are important for firms as technology changes rapidly and as the“cutting edge” moves quickly with frequent innovations. As this process slows, manufacturing becomes more normal and standard and there is less advantage brought by external economies. Instead, firms look for low cost production locations. Since external economies are no longer important, firms find little advantage in being clustered and it is likely that low-wage locations will be chosen.chapter 81.The import demand equation, MD , is found by subtracting the home supply equation from the home demand equation. This results in MD = 80 - 40 x P. Without trade, domestic pricesand quantities adjust such that import demand is zero. Thus, the price in the absence of trade is 2.2.a.Foreign's export supply curve, XS , is XS = -40 + 40 x P. In the absence of trade, the price is 1.b.When trade occurs export supply is equal to import demand, XS = MD . Thus, using theequations from problems 1 and 2a, P = 1.50, and the volume of trade is 20.3.a.The new MD curve is 80 - 40 x (P+t) where t is the specific tariff rate, equal to 0.5. (Note: in solving these problems you should be careful about whether a specific tariff or ad valorem tariff is imposed. With an ad valorem tariff, the MD equation would be expressed as MD =80-40 x (1+t)P). The equation for the export supply curve by the foreign country is unchanged. Solving, we find that the world price is $1.25, and thus the internal price at home is $1.75. The volume of trade has been reduced to 10, and the total demand for wheat at home has fallen to 65 (from the free trade level of 70). The total demand for wheat in Foreign has gone up from 50 to 55.b.andc. The welfare of the home country is best studied using the combined numerical andgraphical solutions presented below in Figure 8-1.P T =1.7550556070QuantityPrice P W =1.50P T*=1.25where the areas in the figure are:a: 55(1.75-1.50) -.5(55-50)(1.75-1.50)=13.125b: .5(55-50)(1.75-1.50)=0.625c: (65-55)(1.75-1.50)=2.50d: .5(70-65)(1.75-1.50)=0.625e: (65-55)(1.50-1.25)=2.50Consumer surplus change: -(a+b+c+d)=-16.875. Producer surplus change: a=13.125. Government revenue change: c+e=5. Efficiency losses b+d are exceeded by terms of trade gain e. [Note: in the calculations for the a, b, and d areas a figure of .5 shows up. This is because we are measuring the area of a triangle, which is one-half of the area of the rectangle defined by the product of the horizontal and vertical sides.]4. Using the same solution methodology as in problem 3, when the home country is very small relative to the foreign country, its effects on the terms of trade are expected to be much less. The small country is much more likely to be hurt by its imposition of a tariff. Indeed, this intuition is shown in this problem. The free trade equilibrium is now at the price $1.09 and the trade volume is now $36.40.With the imposition of a tariff of 0.5 by Home, the new world price is $1.045, the internal homeprice is $1.545, home demand is 69.10 units, home supply is 50.90 and the volume of trade is 18.20. When Home is relatively small, the effect of a tariff on world price is smaller than when Home is relatively large. When Foreign and Home were closer in size, a tariff of .5 by home lowered world price by 25 percent, whereas in this case the same tariff lowers world price by about 5 percent. The internal Home price is now closer to the free trade price plus t than when Home was relatively large. In this case, the government revenues from the tariff equal 9.10, the consumer surplus loss is 33.51, and the producer surplus gain is 21.089. The distortionary losses associated with the tariff (areas b+d) sum to 4.14 and the terms of trade gain (e) is 0.819. Clearly, in this small country example the distortionary losses from the tariff swamp the terms of trade gains. The general lesson is the smaller the economy, the larger the losses from a tariff since the terms of trade gains are smaller.5. The effective rate of protection takes into consideration the costs of imported intermediate goods. In this example, half of the cost of an aircraft represents components purchased from other countries. Without the subsidy the aircraft would cost $60 million. The European value added to the aircraft is $30 million. The subsidy cuts the cost of the value added to purchasers of the airplane to $20 million. Thus, the effective rate of protection is (30 - 20)/20 = 50%.6. We first use the foreign export supply and domestic import demand curves to determine the new world price. The foreign supply of exports curve, with a foreign subsidy of 50 percent per unit, becomes XS= -40 + 40(1+0.5) x P. The equilibrium world price is 1.2 and the internal foreign price is 1.8. The volume of trade is 32. The foreign demand and supply curves are used to determine the costs and benefits of the subsidy. Construct a diagram similar to that in the text and calculate the area of the various polygons. The government must provide (1.8 - 1.2) x 32 = 19.2 units of output to support the subsidy. Foreign producers surplus rises due to the subsidy by the amount of 15.3 units of output. Foreign consumers surplus falls due to the higher price by7.5 units of the good. Thus, the net loss to Foreign due to the subsidy is 7.5 + 19.2 - 15.3 = 11.4 units of output. Home consumers and producers face an internal price of 1.2 as a result of the subsidy. Home consumers surplus rises by 70 x .3 + .5 (6 x.3) = 21.9 while Home producers surplus falls by 44 x .3 + .5(6 x .3) = 14.1, for a net gain of 7.8 units of output.7. At a price of $10 per bag of peanuts, Acirema imports 200 bags of peanuts. A quota limiting the import of peanuts to 50 bags has the following effects:a.The price of peanuts rises to $20 per bag.b. The quota rents are ($20 - $10) x 50 = $500.c. The consumption distortion loss is .5 x 100 bags x $10 per bag = $500.d. The production distortion loss is .5 x50 bags x$10 per bag = $250.。
国际经济学(克鲁格曼)课后习题答案1-8章
第一章练习与答案1 . 为什么说在决定生产和消费时,相对价格比绝对价格更重要?答案提示:当生产处于生产边界线上,资源则得到了充分利用,这时,要想增加某一产品的生产,必须降低另一产品的生产,也就是说,增加某一产品的生产是有机会机本(或社会成本)的。
生产可能性边界上任何一点都表示生产效率和充分就业得以实现,但究竟选择哪一点,则还要看两个商品的相对价格,即它们在市场上的交换比率。
相对价格等于机会成本时,生产点在生产可能性边界上的位置也就确定了。
所以,在决定生产和消费时,相对价格比绝对价格更重要。
2. 仿效图1—6和图1—乙试推导出丫商品的国民供给曲线和国民需求曲线。
答案提示:3. 在只有两种商品的情况下,当一个商品达到均衡时,另外一个商品是否也同时达到均衡?试解释原因。
答案提示:4. 如果生产可能性边界是一条直线,试确定过剩供给(或需求)曲线。
答案提示:5. 如果改用丫商品的过剩供给曲线(B国)和过剩需求曲线(A 国)来确定国际均衡价格,那么所得出的结果与图1 —13中的结果是否一致?答案提示:国际均衡价格将依旧处于贸易前两国相对价格的中间某点。
6. 说明贸易条件变化如何影响国际贸易利益在两国间的分配。
答案提示:一国出口产品价格的相对上升意味着此国可以用较少的出口换得较多的进口产品,有利于此国贸易利益的获得,不过,出口价格上升将不利于出口数量的增加,有损于出口国的贸易利益;与此类似,出口商品价格的下降有利于出口商品数量的增加,但是这意味着此国用较多的出口换得较少的进口产品。
对于进口国来讲,贸易条件变化对国际贸易利益的影响是相反的。
7. 如果国际贸易发生在一个大国和一个小国之间,那么贸易后,国际相对价格更接近于哪一个国家在封闭下的相对价格水平?答案提示:贸易后,国际相对价格将更接近于大国在封闭下的相对价格水平。
& 根据上一题的答案,你认为哪个国家在国际贸易中福利改善程度更为明显些?答案提示:小国9* .为什么说两个部门要素使用比例的不同会导致生产可能性边界曲线向外凸?答案提示:第二章答案1.根据下面两个表中的数据,确定(1)贸易前的相对价格;(2)比较优势型态。
国际经济学克鲁格曼_教材答案解析
Problems and Answers to Chapter 2Q1: Canada and Australia are (mainly) English-speaking countries with populations that are not too different in size (Canada’s is 60 percent larger). But Canadian trade is twice as large, relative to GDP, as Australia’s. Why should this be the case?加拿大和澳大利亚都是英语国家,两国的人口规模也相当(加拿大多60%),但是相对各自的GDP而言,加拿大的贸易额是澳大利亚的两倍,为什么如此?A1:According to Gravity Model, GDP is not the only factor to explain the volume oftrade between two countries, because distance is also an important factor. Consideringthe distance, the transportation cost of Australia is relatively higher than that ofCanada, so the attractiveness of trade is reduced. However, Canada is close to theUSA which is a large economy while Australia is not close to any large economy,making Canada more open while Australia is more autarky.GDP 不是解释两国贸易量的唯一重要因素,距离也是至关重要的因素之一。
《国际经济学》克鲁格曼(第六版)习题答案imsect2
OVERVIEW OF SECTION II: INTERNATIONAL TRADE POLICYSection II of the text is comprised of four chapters:Chapter 8 The Instruments of Trade PolicyChapter 9 The Political Economy of Trade PolicyChapter 10 Trade Policy in Developing CountriesChapter 11 Strategic Trade Policies in Advanced CountriesSECTION II OVERVIEWTrade policy issues figure prominently in current political debates and public policy discussions. The first two chapters of this section of the text are concerned with the instruments of trade policy and the arguments for free trade and managed trade. The second two chapters consider these concepts in the context of specific sets of countries that face common problems. Throughout, the use of case studies provides the student with real world examples that clearly illustrate the theoretical arguments.Chapter 8 discusses various instruments of trade policy including tariffs, quotas, voluntary export restraints, and local content requirements. The effects of these policies on prices and trade volumes are determined in the context of a partial equilibrium framework. The chapter reviews the analytical tools of consumer and producer surplus, and uses these tools to consider the welfare effects of various protectionist measures. The specific incidents of trade restrictions presented as case studies include import quotas on sugar entering United States markets, voluntary export restraints on Japanese autos, and oil import quotas.Chapter 9 presents the set of ideas known as the political economy of trade theory. These ideas enable you to understand why certain trade restrictions exist, despite the force of general economic arguments which suggest that they reduce aggregate welfare. Possible motivations for trade restrictions are identified as those which increase national welfare, such as the optimum tariff, and those which foster either income redistribution or the preservation of status quo. While sometimes politically popular, these motivations for trade restrictions ignore the possibility of retaliation and usually fail tests based upon basic welfare analysis. Trade agreements of the 1990s are discussed, including the Uruguay Round, and distinctionsare made between Free Trade Areas and Customs Unions as well as between trade creation and trade diversion.Chapter 10 considers the possible uses of trade policies to promote the growth of developing economies. The chapter reviews the relative successes of different development strategies. It examines arguments for and the results of import-substituting industrialization. The phenomenon of economic dualism, referring to the coexistence of capital intensive industrial sectors and low-wage traditional sectors, and of uneven development are considered. The chapter concludes with a discussion of export led growth and the experience of the high performing Asian economies.Chapter 11 considers recent controversies in trade policy. The first part of the chapter considers the notion of strategic trade policy, which first arose in the 1990s. Strategic trade policy refers to the use of trade (and other) tools for channeling resources to sectors targeted for growth by industrial country governments. The chapter presents some commonly voiced arguments for intervention in particular sectors of the economy, and then shows how these arguments are critically flawed. The second part of the chapter introduces more sophisticated arguments for strategic trade policy. The most persuasive of these is the existence of some form of market failure. The second part of the chapter considers the impact of rising trade on workers in developing countries, and more broadly, the debate over globalization. This debate has been argued in academia and policy circles, but also on the streets of Seattle, Genoa, and other cities hosting global economic summits.。
《国际经济学》克鲁格曼(第六版)习题答案
CHAPTER 2LABOR PRODUCTIVITY AND COMPARATIVE ADVANTAGE: THE RICARDIAN MODELChapter OrganizationThe Concept of Comparative AdvantageA One-Factor EconomyProduction PossibilitiesRelative Prices and SupplyTrade in a One-Factor WorldBox: Comparative Advantage in Practice: The Case of Babe RuthDetermining the Relative Price After TradeThe Gains from TradeA Numerical ExampleBox: The Losses from Non-TradeRelative WagesMisconceptions About Comparative AdvantageProductivity and CompetitivenessThe Pauper Labor ArgumentExploitationBox: Do Wages Reflect Productivity?Comparative Advantage with Many GoodsSetting Up the ModelRelative Wages and SpecializationDetermining the Relative Wage with a Multigood ModelAdding Transport Costs and Non-Traded GoodsEmpirical Evidence on the Ricardian ModelSummaryCHAPTER OVERVIEWThe Ricardian model provides an introduction to international trade theory. This most basic model of trade involves two countries, two goods, and one factor of production, labor. Differences in relative labor productivity across countries give rise to international trade. This Ricardian model, simple as it is, generates important insights concerning comparative advantage and the gains from trade. These insights are necessary foundations for the more complex models presented in later chapters.The text exposition begins with the examination of the production possibility frontier and the relative prices of goods for one country. The production possibility frontier is linear because of the assumption of constant returns to scale for labor, the sole factor of production. The opportunity cost of one good in terms of the other equals the price ratio since prices equal costs, costs equal unit labor requirements times wages, and wages are equal in each industry.After defining these concepts for a single country, a second country is introduced which has different relative unit labor requirements. General equilibrium relative supply and demand curves are developed. This analysis demonstrates that at least one country will specialize in production. The gains from trade are then demonstrated with a graph and a numerical example. The intuition of indirect production, that is "producing" a good by producing the good for which a country enjoys a comparative advantage and then trading for the other good, is an appealing concept to emphasize when presenting the gains from trade argument. Students are able to apply the Ricardian theory of comparative advantage to analyze three misconceptions about the advantages of free trade. Each of the three "myths" represents a common argument against free trade and the flaws of each can be demonstrated in the context of examples already developed in the chapter.While the initial intuitions are developed in the context of a two good model, it is straightforward to extend the model to describe trade patterns when there are N goods. This analysis can be used to explain why a small country specializes in the production of a few goods while a large country specializes in the production of many goods. The chapter ends by discussing the role that transport costs play in making some goods non-traded.The appendix presents a Ricardian model with a continuum of goods. The effect of productivity growth in a foreign country on home country welfare can be investigated withthis model. The common argument that foreign productivity advances worsen the welfare of the domestic economy is shown to be fallacious in the context of this model.ANSWERS TO TEXTBOOK PROBLEMS1. a. The production possibility curve is a straight line that intercepts the apple axis at 400(1200/3) and the banana axis at 600 (1200/2).b. The opportunity cost of apples in terms of bananas is 3/2. It takes three units of labor toharvest an apple but only two units of labor to harvest a banana. If one foregoes harvesting an apple, this frees up three units of labor. These 3 units of labor could then be used to harvest 1.5 bananas.c. Labor mobility ensures a common wage in each sector and competition ensures the priceof goods equals their cost of production. Thus, the relative price equals the relative costs, which equals the wage times the unit labor requirement for apples divided by the wage times the unit labor requirement for bananas. Since wages are equal across sectors, the price ratio equals the ratio of the unit labor requirement, which is 3 apples per 2 bananas.2. a. The production possibility curve is linear, with the intercept on the apple axis equal to160 (800/5) and the intercept on the banana axis equal to 800 (800/1).b. The world relative supply curve is constructed by determining the supply of applesrelative to the supply of bananas at each relative price. The lowest relative price at which apples are harvested is 3 apples per 2 bananas. The relative supply curve is flat at this price. The maximum number of apples supplied at the price of 3/2 is 400 supplied by Home while, at this price, Foreign harvests 800 bananas and no apples, giving a maximum relative supply at this price of 1/2. This relative supply holds for any price between 3/2 and 5. At the price of 5, both countries would harvest apples.The relative supply curve is again flat at 5. Thus, the relative supply curve is step shaped, flat at the price 3/2 from the relative supply of 0 to 1/2, vertical at the relative quantity 1/2 rising from 3/2 to 5, and then flat again from 1/2 to infinity.3. a. The relative demand curve includes the points (1/5, 5), (1/2, 2), (1,1), (2,1/2).b. The equilibrium relative price of apples is found at the intersection of the relativedemand and relative supply curves. This is the point (1/2, 2), where the relativedemand curve intersects the vertical section of the relative supply curve. Thus the equilibrium relative price is 2.c. Home produces only apples, Foreign produces only bananas, and each country tradessome of its product for the product of the other country.d. In the absence of trade, Home could gain three bananas by foregoing two apples, andForeign could gain by one apple foregoing five bananas. Trade allows each country to trade two bananas for one apple. Home could then gain four bananas by foregoing two apples while Foreign could gain one apple by foregoing only two bananas. Each country is better off with trade.4. The increase in the number of workers at Home shifts out the relative supply schedulesuch that the corner points are at (1, 3/2) and (1, 5) instead of (1/2, 3/2) and (1/2, 5).The intersection of the relative demand and relative supply curves is now in the lower horizontal section, at the point (2/3, 3/2). In this case, Foreign still gains from trade but the opportunity cost of bananas in terms of apples for Home is the same whether or not there is trade, so Home neither gains nor loses from trade.5. This answer is identical to that in 3. The amount of "effective labor" has not changedsince the doubling of the labor force is accompanied by a halving of the productivity of labor.6. This statement is just an example of the pauper labor argument discussed in the chapter.The point is that relative wage rates do not come out of thin air; they are determined by comparative productivity and the relative demand for goods. The box in the chapter provides data which shows the strong connection between wages and productivity.Korea's low wage presumably reflects the fact that Korea is less productive than the United States in most industries. As the test example illustrated, a highly productive country that trades with a less productive, low-wage country will raise, not lower, its standard of living.7. The problem with this argument is that it does not use all the information needed fordetermining comparative advantage in production: this calculation involves the four unit labor requirements (for both the industry and service sectors, not just the two for the service sector). It is not enough to compare only service's unit labor requirements.If a ls< a ls*, Home labor is more efficient than foreign labor in services. While thisdemonstrates that the United States has an absolute advantage in services, this is neithera necessary nor a sufficient condition for determining comparative advantage. For thisdetermination, the industry ratios are also required. The competitive advantage of any industry depends on both the relative productivities of the industries and the relative wages across industries.8. While Japanese workers may earn the equivalent wages of U.S. workers, the purchasingpower of their income is one-third less. This implies that although w=w* (more or less), p<p* (since 3p=p*). Since the United States is considerably more productive in services, service prices are relatively low. This benefits and enhances U.S. purchasing power.However, many of these services cannot be transported and hence, are not traded. This implies that the Japanese may not benefit from the lower U.S. services costs, and do not face an international price which is lower than their domestic price. Likewise, the price of services in United States does not increase with the opening of trade since these services are non-traded. Consequently, U.S. purchasing power is higher than that of Japan due to its lower prices on non-traded goods.9. Gains from trade still exist in the presence of nontraded goods. The gains from tradedecline as the share of nontraded goods increases. In other words, the higher the portion of goods which do not enter international marketplace, the lower the potential gains from trade. If transport costs were high enough so that no goods were traded then, obviously, there would be no gains from trade.10. The world relative supply curve in this case consists of a step function, with as many"steps" (horizontal portions) as there are countries with different unit labor requirement ratios. Any countries to the left of the intersection of the relative demand and relative supply curves export the good in which they have a comparative advantage relative to any country to the right of the intersection. If the intersection occurs in a horizontal portion then the country with that price ratio produces both goods.FURTHER READINGDonald Davis. “Intraindustry Trade: A Heckscher-Ohlin-Ricardo Approach” (working paper, Harvard University).Rudiger Dornbusch, Stanley Fischer, and Paul Samuelson. "Comparative Advantage, Trade and Payments in a Ricardian Model with a Continuum of Goods." American Economic Review 67 (December 1977) pp.823-839.Giovanni Dosi, Keith Pavitt, and Luc Soete. The Economics of Technical Change and International Trade. Brighton: Wheatsheaf, 1988.G.D.A. MacDougall. "British and American Exports: A Study Suggested by the Theory of Comparative Costs." Economic Journal 61 (September 1952) pp.487-521.John Stuart Mill. Principles of Political Economy. London: Longmans Green, 1917.David Ricardo. The Principles of Political Economy and Taxation. Homewood Illinois: Irwin, 1963.。
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克鲁格曼《国际经济学》(国际金融)习题答案要点————————————————————————————————作者:————————————————————————————————日期:23 《国际经济学》(国际金融)习题答案要点第12章 国民收入核算与国际收支1、如问题所述,GNP 仅仅包括最终产品和服务的价值是为了避免重复计算的问题。
在国民收入账户中,如果进口的中间品价值从GNP 中减去,出口的中间品价值加到GNP 中,重复计算的问题将不会发生。
例如:美国分别销售钢材给日本的丰田公司和美国的通用汽车公司。
其中出售给通用公司的钢材,作为中间品其价值不被计算到美国的GNP 中。
出售给日本丰田公司的钢材,钢材价值通过丰田公司进入日本的GNP ,而最终没有进入美国的国民收入账户。
所以这部分由美国生产要素创造的中间品价值应该从日本的GNP 中减去,并加入美国的GNP 。
2、(1)等式12-2可以写成()()p CA S I T G =-+-。
美国更高的进口壁垒对私人储蓄、投资和政府赤字有比较小或没有影响。
(2)既然强制性的关税和配额对这些变量没有影响,所以贸易壁垒不能减少经常账户赤字。
不同情况对经常账户产生不同的影响。
例如,关税保护能提高被保护行业的投资,从而使经常账户恶化。
(当然,使幼稚产业有一个设备现代化机会的关税保护是合理的。
)同时,当对投资中间品实行关税保护时,由于受保护行业成本的提高可能使该行业投资下降,从而改善经常项目。
一般地,永久性和临时性的关税保护有不同的效果。
这个问题的要点是:政策影响经常账户方式需要进行一般均衡、宏观分析。
3、(1)、购买德国股票反映在美国金融项目的借方。
相应地,当美国人通过他的瑞士银行账户用支票支付时,因为他对瑞士请求权减少,故记入美国金融项目的贷方。
这是美国用一个外国资产交易另外一种外国资产的案例。
(2)、同样,购买德国股票反映在美国金融项目的借方。
当德国销售商将美国支票存入德国银行并且银行将这笔资金贷给德国进口商(此时,记入美国经常项目的贷方)或贷给个人或公司购买美国资产(此时,记入美国金融项目的贷方)。
最后,银行采取的各项行为将导致记入美国国际收支表的贷方。
(3)、法国政府通过销售其持有在美国银行的美元存款干预外汇市场,代表美国金融项目的借方项目。
购买美元的法国公民如果使用它们购买美国商品,这将记入美国国际收支账户经常项目的贷方;如果用来购买美国资产,这将记入美国国际收支账户金融项目的贷方。
(4)假定签发旅行支票的公司使用支票账户在法国进行支付。
当此公司支付餐费给法国餐馆时,记入美国经常项目的借方。
签发旅行支票的公司必须销售资产(消耗其在法国的支票账户)来支付,从而减少了公司在法国拥有的资产,这记入美国金融项目的贷方。
(5)、没有市场交易发生。
(6)离岸交易不影响美国国际收支账户。
4、购买answering machine 记入New York 收支账户的经常项目借方,记入New Jersey 收支账户经常项目的贷方。
当New Jersey 的公司将货款存入New York 银行时,记入New York 的金融项目的贷方和New Jersey 金融项目的借方。
如果交易用现金进行支付,则记入New Jersey 金融项目的借方和New York 金融项目的贷方。
New Jersey 获得美元现钞(从New York 进口资产),而New York 则减少了美元(出口美元资4 产)。
最后的调整类似于金本位制下发生的情况。
5、(1)、非储备金融项目余额为盈余5亿美元,而经常项目赤字10亿美元,所以当年Pecunia 国际收支余额(官方结算余额)为-500万美元。
该国不得不为弥补经常项目赤字提供一亿美元的资金,所以该国当年净国外资产减少1亿美元。
(2)、Pecunia 中央银行为经常项目赤字提供的资金不能由私人资本流动来弥补。
仅仅当外国中央银行需要Pecunia 资产时才能使Pecunia 中央银行避免使用5亿美元储备来为弥补经常项目赤字提供资金。
因此,Pecunia 中央银行储备资产减少了5亿美元,这部分在其国际收支表上将以官方资本形式流入(同样的数量)。
(3)、如果外国官方资本流入Pecunia 6亿美元,则该国有1亿美元的国际收支盈余。
即,该国需要10亿来弥补经常项目赤字,但有11亿流入了该国。
因此,Pecunia 中央银行必须使用额外的一个亿借贷给国外从而增加其储备。
被外国中央银行购买的Pecunia 资产作为流出进入该他们国家的国际收支账户借方。
基本原理是该交易导致外国对出售资产方的Pecunia 支付。
(4)、与非中央银行交易一起,Pecunia 国际收支账户将表现为外国官方储备资产增加6亿美元(金融项目贷方或资本流入)和Pecunia 在国外持有的官方储备资产增加1亿美元(金融项目借方或资本外流)。
当然,净资本流入1亿美元仅仅用来弥补经常项目赤字。
6、从长期来看,经常项目赤字或盈余是一种非稳定的状态。
下面是一个赤字被重视例子。
例如,为了未来有较高的国民收入而现在借款提高其生产能力。
但是,经常项目赤字的任何时期,为了支付对外国人发生的债务,意味着由于缺少收入而减少相应时期的支出。
在缺乏良好的投资机会时,相对于收入,一国最好的方式可能是在一段时期内进行消费方面的调整。
一国中央银行持有的外汇储备随着其官方结算余额非零而发生变化。
中央银行利用外汇储备来影响外汇汇率。
外汇储备的减少将会限制中央银行影响或盯住汇率的能力。
对于一些国家(特别是发展中国家),当向国外借款困难时,中央银行储备是保持消费与投资的重要方式。
高储备也可以起到传递信号的作用,使国外的借款者确信对该国信贷是值得的。
7、官方结算余额也称为国际收支余额,它表示相对于由外国政府机构持有的美元储备变化,由美国政府机构(如美联储、财政部)持有的国际储备的净变化额。
这个账户提供了外汇市场上干预程度的部分情况。
例如,假设Bundesbank 购买美元并存入London bank 的欧洲非美国银行的账户。
虽然这项交易是干预的形式,但并不会反映在美国官方结算余额。
相反,当London bank 将这笔存款划给其在美国的账户,此交易将以私人资本流的形式出现。
8、可以,如果资本与金融项目盈余超过经常项目赤字。
国际收支余额等于经常项目盈余加上资本金融项目盈余。
如:经常项目赤字100万美元,但存在比较大的资本流入且资本与金融项目盈余102万美元,故国际收支存在2万的盈余。
这个问题可以用来介绍外汇市场干预(第17章)。
在20世纪80年代的上上半期,美国政府对外汇市场无任何干预。
1982-1985年间,实际数字显示国际收支存在较小的盈余,教材结果是国际收支余额为零,而这些年经常项目存在明显的较大赤字。
5 因此,1982-1985年美国资本流入超过了其经常项目的赤字。
第13章 汇率与外汇市场:资产方法1、汇率为每欧元1.5美元时,一条德国香肠bratwurst 等于三条hot dog 。
其他不变时,当美元升值至1.25$per Euro, 一条德国香肠bratwurst 等价于2.5个hot dog 。
相对于初始阶段,hot dog 变得更贵。
2、63、25%;20%;2%。
4、分别为:15%、10%、-8%。
5、(1)由于利率相等,根据利率平价条件,美元对英镑的预期贬值率为零,即当前汇率与预期汇率相等。
(2)1.579$per pound6、如果美元利率不久将会下调,市场会形成美元贬值的预期,即e E 值变大,从而使欧元存款的美元预期收益率增加,图13-1中的曲线I 移到I ',导致美元对欧元贬值,汇率从0E 升高到1E 。
131-图 7、(1)如图13-2,当欧元利率从0i 提高到1i 时,汇率从0E 调整到1E ,欧元相对于美元升值。
I 'I0E 1E $/euroE i6图13-2(2)如图13-3,当欧元对美元预期升值时,美元存款的欧元预期收益率提高,美元存款的欧元收益曲线从I '上升到I ,欧元对美元的汇率从E '提高到E ,欧元对美元贬值。
133-图8、(a)如果美联储降低利率,在预期不变的情况下,根据利率平价条件,美元将贬值。
如图13-4,利率从i 下降到i ' ,美元对外国货币的汇价从E 提高到E ',美元贬值。
如果软着陆,并且美联储没有降低利率,则美元不会贬值。
即使美联储稍微降低利率,假如从i 降低到*i (如图13-5),这比人们开始相信会发生的还要小。
同时,由于软着陆所产生的乐观因素,使美元预期升值,即e E 值变小,使国外资产的美元预期收益率降低(曲线I 向下移动到I '),曲线移动反映了对美国软着陆引起的乐观预期,同时由乐观因素引起的预期表明:在没有预期变化的情况下,由利I 'EE 'euro/$E I iIE 1E euro/$E rate of return(in euro)0i 1i7 率i 下降到*i 引起美元贬值程度(从E 贬值到*E )将大于存在预期变化引起的美元贬值程度(从E 到E '')。
134-图(b)经济衰退的破坏性作用使持有美元的风险增大。
相对于低风险资产,高风险资产必须提供额外的补偿,人们才愿意持有它。
在预期不变前提下,只有美元现汇贬值,才能提高风险升水水平。
因此,如果美国经济衰退将会使美元贬值。
如果美元软着陆就以避免美元的大幅贬值。
9、欧元风险更小。
当美国居民持有其他财富的收益率升高时,欧元贬值使欧元资产的美元预期收益率提高,使欧元升值,从而减少资产损失。
I*E E$/foreign currencyE i 'iR ate of return(in dollars)I 'i E ''135-图IE 'E$/foreign currencyE i 'iRate of return(in dollars)8 因此,持有欧元能减少财富的可变性。
10、本章说明,即使最终交易是非美元结算的,银行间的大部分外汇交易均与美元有关(银行间外汇交易占外汇交易的大部分)。
美元的关键作用使美元成为载体货币。
由于人们更愿意用其他货币交换成美元,使美元这种载体货币成为最具流动性的货币。
所以,相比于墨西哥比索,美元更具流动性,所以人们更愿意持有美元。
与墨西哥比索相比,由于美元流动性更大,持有美元的风险性更小,所以即使美元存款利率较低,仍然具有更强的吸引力。
当国际资本市场一体化加快,相对于日元存款,美元存款的流动性优势将逐渐减少。
欧元区代表与美国一个大的经济体,其有可能与美元一样承担载体货币作用,进而减少美元的流动性优势。